Abstract 253: Mammary tumorigenesis causes bone loss and dietary selenium supplementation does not affect such bone loss in male MMTV-PyMT mice

Abstract

Abstract Cancer progression is accompanied by wasting that eventually results in cachexia characterized by significant weight loss and multi-organ functional failures. Limited clinical trials indicate that bone is adversely affected by cancer-associated wasting. To determine the effects of breast cancer on skeletal health, we performed micro-computed tomographic analysis of femurs and vertebrae collected from a recently completed study showing that dietary supplementation with selenium (methylseleninic acid, 2.5 mg Se/kg) reduced male mammary tumorigenesis in MMTV-PyMT mice. Compared to age-matched non-tumor-bearing mice (MMTV-PyMT negative), the presence of mammary tumors significantly reduced bone volume fraction, trabecular thickness and bone mineral density and increased the structure model index (an indicator of the plate- and rod-like geometry of trabecular structure) in femoral trabecular bone. Mammary tumor development did not affect vertebral trabeculae nor femoral and vertebral cortical bone, except it significantly reduced cortical bone thickness of vertebrae. There were no differences in aforementioned measurements between groups with or without selenium supplementation. In conclusion, mammary tumorigenesis causes bone loss and dietary selenium supplementation at 2.5 mg Se/kg, which is antitumorigenic, does not affect mammary tumor-associated bone loss in this male MMTV-PyMT breast cancer model. Citation Format: Lin Yan. Mammary tumorigenesis causes bone loss and dietary selenium supplementation does not affect such bone loss in male MMTV-PyMT mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 253. doi:10.1158/1538-7445.AM2017-253